Polyamide film coated with vinylidene chloride copolymer mixture and method for producing the same

Abstract

Disclosed is a polyamide film coated with a vinylidene chloride copolymer mixture, wherein: on at least one side of a biaxially stretched polyamide film, a vinylidene chloride copolymer mixture layer in which no thermal crosslinking agent is copolymerized is formed by coating without through an intermediary of a primer layer; the vinylidene chloride copolymer mixture is a mixture including two or more vinylidene chloride copolymers; and one of the vinylidene chloride copolymers has a crystal melting point of 170° C. or higher and 210° C. or lower and is contained in an amount of 25 to 45 parts by mass in relation to 100 parts by mass of the vinylidene chloride copolymer mixture.

The invention claimed is: 
     
       1. A method for producing a nylon 6 film coated with a vinylidene chloride copolymer mixture, comprising:
 coating an unstretched nylon 6 film with a latex of a vinylidene chloride copolymer mixture without a primer layer; 
 regulating a water content of the unstretched nylon 6 film to be 2 to 10% by mass and a degree of crystallization of the unstretched nylon 6 film to be 15.6 to 30%; and 
 biaxially stretching the nylon 6 film, wherein 
 the vinylidene Chloride copolymer mixture comprises two or more vinylidene chloride copolymers having no thermal crosslinking agent copolymerized therewith, 
 one of the vinylidene chloride copolymers has a proportion of vinylidene chloride falling in a range of 95 to 99% by mass, exhibits the highest crystal melting point among the vinylidene chloride copolymers, has a crystal melting point of not lower than 170° C. and not higher than 210° C., and is contained in an amount of 25 to 45 parts by mass in relation to 100 parts by mass of the vinylidene chloride copolymer mixture, and 
 another of the vinylidene chloride copolymers has a proportion of vinylidene chloride falling in a range of 80 to 95% by mass.